The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 05, 1991
Filed:
Aug. 25, 1989
John R Dukes, Worthington, OH (US);
Mason L Thompson, Worthington, OH (US);
Process Automation Business, Inc., Columbus, OH (US);
Abstract
Method and apparatus for measurement and control of an industrial process by detecting the average transmittance of a radiation beam which passes through the process material. A radiation source (28) having an intensity I.sub.o is positioned on one side of the material to be measured and a suitable radiation detector (32) is positioned on the other side. The transmitted radiation intensity, I, is measured by the sensor. An index Z commensurate with the degree of nonuniformity of the variable in the material is determined, and a process signal is generated from a quantitative relationship among I, I.sub.o, and the index Z. In a first embodiment implementedd in a system for measurement and control of the basis weight of paper in a paper production process, the index Z is indicative of the nonuniformity of the material mass distribution in the sheet and is determined by measurements with a separate formation gauge operating on-line with, but independently of, the basis weight sensor. In a second embodiment of the invention implemented in such a paper making process, the index Z commensurate with the degree of nonuniformity for the mass in the material, is derived from the standard deviation of the detected radiation intensity signal, or the equivalent standard deviation of the basis weight output signal.